I picked up an '06 LeMond Buenos Aires (with 25mm Bontereger tires) back in April and have just about 500 miles on it. New old stock bikes can be a great value. A current model year Buenos Aires costs nearly a grand more than what I paid. I would NOT have gotten that past my wife... this was already at the upped end of what I throught she'd accept.
I weight 215 Lbs and always carry two water bottles, and have a (10 Lbs) handlebad bag with me all the time. When I started looking at road bike I was VERY worried about the skiny tires and low count spokes. Every local bike store told me not to worry. I managed to break a few spokes on my Gary Fisher Nirvanna which has 32 spokes front and rear, so I had experience with breaking spokes. So far it appears that the higher end bikes (over $1000) come with much higher quality wheels than your mid price ($500) hybrids. The Buenos Aires does come with slightly upgraded wheels over the Alp d'Heuz I was considering, but it does appear that these wheels can take the load. The roads around here in the Snow Belt are not always the greatest so the bike does take a bit of a beating, but so far so good. I have had excellent service from my LBS in the past when I've had wheel problems so I knew they would take care of me if I ran into problems.
Whenever I switch over to the road bike I am amazed at how easy you get up to speed, and how fast you can go in the more aerodynamic position, and with the higher quality bearings, etc. The hybrid is still the all weather "war horse," but it sure is fun to ride a thoroughbred on the longer rides.
Happy riding,
André